Milling machine for grain



Dec. 27, 1938. .A. FREROTTE 2,1 1,647

MILLING MACHINE FOR GRAIN Filed July 2, 1957 4 Sheets-Sheet 1 I N V E NTO R Auausr; FREROTTE Arron/V536 Dec. 27, 1938. A. FREROTTE 2,141,647

' MILLING MACHINE FOR GRAIN Filed July'2, 1937 4 Sheets-Sheet 2 mvcwf RHUGl/STE FRERorrE A. FR EROTTE I Dec. 27, 1938.

MILLING MACHINE FOR GRAIN 4 Sheets-Sheet 3 I N V E N TO R Hum/51EFE'EEGTTE Filed July 2, 1957 HTTOIE'NEYS Dec. 27, 1938. A. FREROTTE'2,141,647,

MILLING MACHINE FOR GRAIN Filed July 1937 4 Sheets-Sheet 4 INVENTORfluausrs FREROTTE izu wr ATTORNEY:

Patented Dec. 27, 1938 UNITED s'rres MILLING MACHINE FOR GRAIN AugusteFrrotte, Liege, Belgium, assignor to Henry Simon Limited, Stockport,England, a

British company Application July 2, 1937, Serial No. 151,652 In BelgiumJuly 25, 1936 Claims.

This invention is for improvements in or relating to a milling machinefor grain of the kind comprising two milling rollers, one of which isrotatable about a fixed axis and the other of 5i; which is movabletowards and away from the first said roller and a train of gears andpinions connecting together two gear-wheels fixed respectively to thetwo rollers. The movement of the roller is required for two purposes. Iten- 1o ables the pressure on the material being ground to'be regulatedand the extent of movement for that purpose is quite small. It alsoenables the rollers to be brought closer together after they have beenreduced in diameter by re-bufilng or 1 re-grooving.

According to this invention, a milling machine of the kind referred toabove is characterized in that the movable roller is so mounted and thepinion which meshes with the gear-wheel on the movable roller is solocated that the short path of movement of the axis of the movableroller during the adjustment of the distance between the rollers, ashereinbefore described, is substantially parallel with or deviateslittle from a line parallel with the common tangent of the contactingpitch circles of said pinion and gearwheel. It will be appreciated thatwith this ar-- r-angement the variation inthe extent of mesh occasion dby the movement of the roller for adv justment of the pressure will benegligible and thus there will be little tendency for wear of thegear-teeth. It will further be appreciated that it is not usual to runthe machine when the rollers are fully separated. If desired, smallerpitched teeth may be employed than usual.

In one arrangement of carrying out the invention, the movable roller andits gear-wheel may be mounted to swing about an axis disposed on theopposite side of the roller axis to that on which is-located the gearpinion which engages the roller gear-wheel, which axis of swing, axis ofthe movable roller and the axis of the pinion gear-wheel liesubstantially line when the gear-wheel and pinion are in full mesh,which 45, line is substantially at right angles to a line joining theaxes of the two rollers.

Another feature of the invention consists in locating said gear-wheelsand gear-pinions-in a casing comprising separable upper and lower 50,parts, the lower of which parts comprises an oilwell into which a partof the gearing clips and which is pivotally secured to the upper casingand in the provision of means for so locating the lower part: in an openposition that the oil'is V 55gretained therein. One of said'gearepinions-may be driven directly by anelectric motor which iscarried by said casing.

Yet a 'further feature of the invention, in-a milling machine whereintwo pairs of milling rollers are provided, for-example parallel with oneanother, consists in that the two pairs of rollers are drivenrespectively by two motors. The two trains of gears and the two motorsmay all be arranged at one end of the machine.

In a milling machine in which hand-controlled means are provided forvarying the distance apart oisaid rollers and in which an electric motoris arranged to drive said rollers, a feature of the invention consistsin the provision of a switch in circuit with the motor and so operatedby said hand-controlled meanst'hat the circuit is closed when therollers are brought together. For example, the'switch-is closed when therollers are brought together; Conversely, the switch is opened whenthe-rollers are moved apart.

In an arrangement in which the movement of the movable roller isefiected by an operating arm which extends out through a slot in thecasing surrounding the rollers, -a feature of the invention consists inproviding said arm with a shield which is arranged to obscure said slotfor all positions of said arm.

' "The followingis a description of one form of construction for amilling machine reference being made to the accompanying drawings, inwhich:

Figure 1 is an end elevation of a machine having two pa-irs of rollers,on one side of the machine a casing containing the gearing being shownin section, while on the other side of. the machine the top* part of thegearing casing has been removed while the'lower part has been swungdownwardly,

Figure '2 is a vertical section through the casing and in a planepassing through the slot in which the control lever operates,

Figure 3 is a plan view of the hand control means shown in Figure 2showing parts thereof in section on the line 33, and

Figure 4 is a section on the line 4- of Figure 2. throughthe clutchmechanism.

As'will be seen from Figure 1, two pairs of independently-driven rollersare'provided in the one machine casing. It is usual in such anarrangement for'ra roller of one of the pairs to receivelits drive froma belt-pulley fixed to its shaft at one end of the machineandiora rollerofzthe other pair to receive its drive from a pulley'fixed to its shaftat the other-end ofvthe machine. It, is :alsosknown-to "connecttheisecnd roller of each pair through a train of gears to the first saidroller so as to provide a suitable speed ratio. In the present form ofconstruetion it will be noted that both pairs of rollers receive theirdrive from the same end of. the machine.

Each pair of rollers comprises an upper roller 3 which is arranged torotate about a fixed axis and a lower roller 2 which is so. mounted asto be capable of movement towards and away from the roller 3. Therollers are gear-connected together by a gearewheel l0 fixed to rotatewith the roller 3, an intermediate pinion 8, a compoundintermediatepinion having one portion !2 gearing with the pinion 8 and anotherportion 9 gearing with a gear-wheel l4 fixed to rotate with the roller2. The roller 2 and thegearwheel I4 are mounted to swing about an axis[8. This axis and the axes of the gear-wheel l4 and pinion 9 arearranged substantially in line when the two rollers are in contact,which line is ap-' proximately at right-angles to a line passing throughthe axesvof the two rollers. Thus, as the movable roller 2 is movedtowards and away from the roller 3 to the small extent necessary toadjust the pressure on the material being ground, the path of movementof the axis of the roller 2 deviates but little from a line parallelwith the tangent common to the contacting pitch circles of thegear-wheel I4 and pinion 9. The further the axis I8 is arranged from theaxis of the roller 2, the more nearly will said path of movement beparallel to the common tangent.

It will be noted that the gear-train is enclosedin a two-part casing,the upper part I of which is fixed in relation to the machine frame andthe lower part 5 of which casing is mounted to swing about a pivot pin6'. The two parts of the casing are secured together by set-screws l9.When closed, the dividing line between the two parts of the casing isinclined to the vertical and a stop 20 is provided on the end wall ofthe machine to engage an abutment on the bottom part of the lower casingso that when it is swung downwardly the oil contained in'the lower partof the casing is retained therein. The compound pinion 9, l2 and theintermediate pinion 8 are M andthe gear-wheel l0, respectively, whenthelower part of the casing is lowered. The upper part of the casing I canbe detached from the main body of the machine; thus, when it is detachedand when the lower part of the casing is swung downwardly, ready accessmay be gained to the gear-wheels and pinions for the purposes ofcleaning and inspection. Furthermore, the arrangement enables therollers to be withdrawn through apertures in the side wall of the maincasing after the removal of the bearings for the roller shafts. Mountedon the lower part 5 of each casing is a driving motor 9a to a shaft ofwhich is secured the pinion 5. As already indicated, the lower part ofthe casing forms an oil-bath into which the compound gear 9, l2

dips and thus distributes oil to the other wheels 7 of the gear-train.With this arrangement, both the driving motors and the transmissiongears are arranged at oneend of the machine. As already indicated, theroller 2 and the gear-wheel Hi are arranged to swing about a pivot axisl8.

This is effected by'mounting them on a cranked lever 2| which at one endis pivotally mounted about the axis' 18 and the other end 'of which isforked and 'straddles a .r0d'22 having abut ments 23 and 24 arranged'oneither side of the fork. The rod may be moved in an up-and-downdirection by an eccentric, shown dotted, mounted on a cross shaft 25(see Figure 2) to which is attached an operating lever I5. A fineadjustment for moving either end of the roller 2 is provided by ascrew-and-nut mechanism associated with the rod 22 at each end of themachine and with abutments 23 and. 24, which screw-and-nut mechanism isoperated by a hand-control wheel 26; A fine adjustment for movement ofthe roller 2 as a whole towards or away from the roller may be effectedby the rotation of the cross shaft 25 and eccentric by means of ascrew-and-nut device 34 which forms a connection between the operatinglever l5 and a lever arm fixed to the cross shaft. The operating leverl5, in addition to controlling the distance apart of the rollers 2 and3, operates a clutch associated with feeding mechanism. The

operating lever i5 has a boss 38 provided with a hole39 having its axesparallel but displaced from, the axis of the cross-shaft, which hole isengaged by a pin 30 at the end of the link 4|. lI'he other end of thelink is adjustably connected to a tie member 42 which is slotted at bothends at 43. Two studs 44 extend through the slots and engagerespectively the link 4| and a rod 45; The rod extends through a slot 46in a lever arm 47. The rod is encircled by a. compression a washer 50which engages the end of the lever arm 41. The rod is engaged on theopposite side of the lever arm to the washer 50 by nuts 5| and a washer52 which is disposed between a nut and lever arm. The lever arm 4'! isattached at one end of a short stub shaft 53 which is rotatably mountedin a bearing member 54 attached to a gear casing 55. Projecting from theinner end of the stud shaft is a pin 56 which engages a circumferentialslot 57 formed in a clutch member 58 rotatably mounted on a drivingshaft 59, whereby the clutch member may be 'moved axially along theshaft into and out of engagement with another clutch member 60 "fixed tothe driving shaft 59 driven by'the electric'motor 9a driving thegrinding rollers 2 and 3 by suitable belt and pulley drive 66 and 61shown in Figure 2,but omitted from Figure 1 for convenience. Thefirst-clutch member 58 is fixed to a pinion 6| which is arranged toengage two spur-wheels 62 and 63 arranged on either side of it. Thesetwo'spur-whe-els are fixed to the shafts E i-and 55, respectivelyyof thetwo feed rollers 3i and 32. I V

The operating lever [5 also controls an electric switch I! (see Figure2) in circuits with the driving motor 9a. For this purpose the lever isprovided.- with' a cam l6 which is arrangedto come into contact with aspring-controlled switch-arm 33 when the rollers have been separated.For this purpose thelever arm is provided at a controlled rate by thefeed rollers 3| and 32 which drive through suitable gearing from the.-motors 9a. Thus the feed of materialwill be stopped when the circuitofthe motor is broken upon separation of the rollers and started againwhen the rollers are'brought together. The cirshown in Figure 2. 7

cuit connections of the switch and motor are spring 48 which at theoneend abuts a shoulder I 59 on the rod and at the other abuts againstAs will be seen from Figure 2, the cross shaft 25, on which theoperating lever I is mounted, is ar-' ranged within the main casing ofthe machine and the lever arm extends out through a slot formed betweenthe parts 21 and 28 of said main casing. In order to prevent dust anddirt entering the machine through this slot, the lever arm has attachedthereto two shields 29 and 30 which between them serve to obscure theslot for any position of the lever I5.

I claim:-

1. A milling machine comprising two milling rollers, a fixed mountingfor one roller, a movable mounting for the other roller, hand-controlledmeans associated with the movable mounting for adjusting the distanceapart of the rollers, gearing between said rollers which permitsmovement of the movable roller without disengagement of the gearing,means for feeding the material to be ground to the rollers, an electricmotor adapted to drive both one of the members of the gearing and saidfeeding means, an electric switch in circuit with said motor and sooperatively connected to the hand-controlled means that the circuit isclosed when the rollers are brought together and opened when the rollersare moved apart.

2. A milling machine comprising two milling rollers, a fixed mountingfor one roller, a movable mounting for the other roller, a gear-wheelfixed to each roller, a train of intermediate pinions connecting saidgear-wheels, means for so constraining the movement of the movablemounting that the common tangent of the pitch circles of the gear-wheelon the movable roller and the pinion with which it engages issubstantially parallel with the initial direction of movement of theroller, upper and lower casing parts, the lower of which parts supportssaid intermediate pinions and constitutes an oil well, an electric motormounted on said lower casing part and connected to one of said pinions,which lower casing part is pivotally mounted so that the pinions may bewithdrawn from engagement with the gear-wheels to an extent whichpermits axial removal of the rollers and means for locating the lowercasing part in an open position so as to retain the oil therein. I

3. A milling machine comprising two milling rollers, a fixed mountingfor one roller, a movable mounting for the other roller, hand-controlledmeans associated with the movable mounting for adjusting the distanceapart of the rollers, gearing between said rollers which permitsmovement of the movable roller without disengagement of the gearing,means for feeding the material to be ground to the rollers, an electricmotor adapted to drive both one of the members of the gearing and saidfeeding means, an electric switch in circuit with said motor and sooperatively connected to the hand-controlled means that the circuit isclosed when the rollers are brought together and opened when the rollersare moved apart, and means for closing the switch at the commencement ofthe movement of the rollers together and to open it when the rollers aremoved almost to their full extent apart.

4. A milling machine comprising two milling rollers, a fixed mountingfor one roller, a movable mounting for the other roller, hand controlmeans associated with the movable mounting for adjusting the distanceapart of the rollers, a gearing between said rollers which permitsmovement of the movable roller without disengagement of the gearing, twofeed rollers for feeding the material to be ground to the millingrollers, an electric motor adapted to drive one of the members of thegearing for the milling rollers and also to drive the feed rollers, aclutch between the motor and the feed rollers and operatively connectedto said hand control means, an electric switch in circuit with saidmotor and also operatively connected to said hand control means wherebythe clutch is arranged to be disengaged before the milling rollers arefully separated and before the electric switch is opened.

5. A milling machine comprising two milling rollers, a fixed mountingfor one roller, a movable mounting for the other roller, hand controlmeans associated with the movable mounting for adjusting the distanceapart of the rollers, a casing surrounding said rollers and formed witha slot through which said hand control means extend, a shield attachedtothe hand control means of such a size as to cover said slot-for allpositions of the control means and so positioned as to form an efiectiveseal with said casing, gearing between said rollers arranged to remainin engagement during the movement of said movable roller, an electricmotor for driving said gearing, an electric switch in circuit with saidmotor and means operated by said hand control means for closing saidswitch at the commencement of the movement of the rollers together andfor opening it when the rollers are moved almost to their full extentapart.

AUGUSTE FREROTTE.

